The TPS54040 device is a 42-V 0.5-A step-down regulator with an integrated high-side MOSFET. Current mode control provides simple external compensation and flexible component selection. A low-ripple pulse-skip mode reduces the no load, regulated output supply current to 116 μA. Using the enable pin, shutdown supply current is reduced to 1.3 μA, when the enable pin is low.

Undervoltage lockout is internally set at 2.5 V, but can be increased using the enable pin. The output voltage startup ramp is controlled by the slow start pin that can also be configured for sequencing/tracking. An open drain power good signal indicates the output is within 93% to 107% of its nominal voltage.

A wide switching frequency range allows efficiency and external component size to be optimized.